Envelop-fastener.



L. F. THIEL.

ENVELOP FASTENER.

APPLICATION FILED MAR. 26. 1911.

Patented Aug. 27, 1918.

2 SHEETS-SHEET I. I 1 a m: ucnms Prrsns ca. PHuTD-L! 1:10.. WAsl-Imn'mn.1i 0.

L. F. THFEL.

ENVELOP FASTENEB. APPLICATION FILED umze. um;

1,277,156. Patented Aug. 27, 1918.

2 SHEETSSHEET 2- LOUIS F. TI-IIEL, OF CHICAGO, ILLINOIS.

ENVELOP-FASTENER.

, Specification of Letters Patent 7 Patented; A11 2'7, 1918.

Application filed. March 26.1917. Serial No. 157,549.

numerals of reference marked thereon, which form a part of thisspecification.

This invention. relates to an improved form of locking envelop, and moreparticularly to the fastening or locking means of the envelop wherebythe envelop may be unreleasably locked in closed position, therebyproducing an envelop permitting access to the interior of the same afterit has been closed only by destroying the fastening means or the envelopitself, "thus affording a means for sending documents, papers, or otherthings adapted to I fit within an envelop without having the sameinterfered with before the delivery thereof to the proper person'forwhom they were intended.

It is an object of this invention to construct a locking envelop adaptedto be opened, after the same has been closed, only by destroying theenvelop.

It is also an object of this invention to provide an envelop havinginterfitti'ngf means thereon adapted to unreleasably engage one anotherto lock the envelop.

Another object of this invention is the construction of an envelopprovided with means on the back thereof adapted to engage a means on theenvelop flap to hold the envelop permanently locked.

It is furthermore an object of this invention to construct hookedlocking means for an envelop adapted to lockingly engage a means on theenvelop flap to permanently hold the envelop locked.

It is an important object of this invention to provide a locking meansfor an envelop, simple and inexpensive of. construction, adapted topermanently hold the envelop locked.

Other and further important objects of this invention will be apparentfrom the disclosures in the drawings andspecification.

The invention (in a preferred form) is illustrated in the drawings, andhereinafter more fully described.

On the drawings:

Figure 1 is a rear elevational view-of a closed envelop, having alocking means thereon embodying the principles of this 1nvention."

Fig. 2 is a section taken on line 22 of Fig. 1.. g

Fig. 3 is an enlarged fragmentary vertical section taken through thelocking means of the envelop, with the locking parts in initialposition.

n Fig. 4 is a similar section showing the next step in the lockingoperation.

Fig. 5 is a similar section showing the locking parts engaging oneanother.

Fig. 6 is a section similar to that shown in Fig. 3, but showing theparts permanently locked to' prevent opening of the envelop. I i

Fig. 7 is a plan view of the flap opened.

As shown on the drawings:

The reference numeral 1, designates the front sheet of, an envelop, madeofheavy paper, cloth or other suitable material, having integrallyformed on each end thereof a rear side flap 2, each. of which is bentinwardly along its integral edge of lie flat against the inner surfaceof the front'sheet 1. Also integrally formedon the front sheet at thelower edge thereof is a back piece 3,

bent inwardly to lie fiat against the side flaps 2, and is'rigidlysecured thereto'by glue or other suitable means to form the body of theenvelop. The upper edge of the back piece is parallel to the base of theenvelop and has integrally formed thereon a short distance from each endthereof a rearwardly or outwardly directed hook or male looking memberl.

Integrally formed along the upper edge of the front sheet 1, is a topflap 5, bent rearwardly and downwardly, and then inwardly and upwardlyupon itself to form a locking flap 6, provided with a notch or opening7, near each end thereof alined with one another and adapted to registerwith the hooks 4, when the locking flap 6,

The operation is as follows:

In the form of the device shown in Figs. 1 to 6, inclusive, after thebody of the envelop has been filled with papers ,or documents to bemailed or expressed, the top flap is bent toward the back piece 3, ofthe envelop into a position wherein the openings 7, of the looking flap.6, register with the hooks l, as shown in Fig. 3. The hooks are thenforced through said openings into a position in which the hooks contactor rest against the latches 9, as shown in Fig. 4%. The back piece 3, isnow pulled down, thus forcing the hooks 4, to springingly engage belowthe lower ends of the latches 9, as shown in Fig. 5. By pulling the backpiece 3, down farther, the upper bent portions of said hooks seat uponthe lower edges of said openings ,7, as shown in Fig. 6, thuspermanently locking the envelop, and permitting the contents of theenvelop to be removed only by destroyingthe envelop or the locking meansthereof. This permanent locking is due to the fact that when thefastening means for the envelop are in the position shown in Fig. 6, thehooks are prevented from moving upwardly by the latches 9, which engagein said hooks, thereby making it impossible to withdraw the lockinghooks through the openings 7 when once they have been moved into lockingposition.

I am aware that various details of construction may be varied through awide range Without departing from the principles of this invention, andI therefore do not purpose limiting the patent granted otherwise thannecessitated by the prior art.

I claim as my invention: 1. In a device of the class described anenvelop body, a locking member integral with the'body, a double flapmember, one mem her having apertures therein through which the lockingmembers are adapted to be inserted and hooks secured to the other flapmember to engage said locking members.

2; A locking envelop comprising a front sheet, end and back sheets,hooks formed integral with the back sheet at the upper edge thereof, afolded flap having apertures to receive the hooks therethrough, and areinforcing strip secured to the flap having integral downwardlydirected lugs, each lug shaped at its lower end to form a tongue toengage the respective hook.

3. In a device of the class described, an envelop body havingoverlapping parts, a locking memberon one of the parts, the other parthaving a doubled portion with an aperture therein through which thelocking member is adapted to be inserted, and a shiftable latch withinthe doubled portion adapted to engage the said locking member.

41-. A locking envelop having overlapping parts, a locking member on oneof said parts having a plurality of reversely hooked portions, the otherpart having a doubled portion provided with an intermediate space, and amovable part within the doubled portionadapted to engage thehookedlocking member.

In testimony whereof I have hereunto subscribed my name in the presenceof two subscribing witnesses.

LOUIS F. THIEL.

Gopies of this patent may be obtained for five cents each, by add essingthe Commissioner of latents,

\ Washington, D, (3.

